Control system

Abstract

The present application relates to a control system. A control section, after a stop advance sign section is detected by a sign detection section, in a case where a stop position sign section is detected by the sign detection section, executes travel stop processing that causes travel of a traveling section to stop, and after travel of the traveling section caused by the travel stop processing is stopped, executes transfer processing that causes a transfer section to perform transfer of an article. The control section, in a case where the stop position sign section is detected by the sign detection section, although a travel distance from a position where the stop advance sign section is detected by the sign detection section is below a determination distance that is set to be less than an advance distance, after travel of the traveling section caused by the travel stop processing is stopped, instead of the transfer processing, executes abnormality notification processing that notifies an upper control unit of an abnormality occurrence.

Description

Technical Field

[0001] This invention relates to a control system for controlling a goods transport vehicle that travels along a predetermined path to transport goods. Background Technology

[0002] An example of such a control system is disclosed in Japanese Patent Application Publication No. 4-123113 (Patent Document 1). In the following description of this background art, symbols from Patent Document 1 will be referenced in parentheses.

[0003] Patent Document 1 discloses a control system for controlling a moving vehicle (A) that travels along a path to transport goods. The path of the moving vehicle (A) is configured to pass through multiple stations (ST) for loading and unloading of goods, and the moving vehicle (A) is controlled to stop at a location (hereinafter referred to as a "stop location") of a station (ST) with a target. In the control system of Patent Document 1, a marker (M) set at a position corresponding to the stop location is used to control the moving vehicle (A) to stop at the stop location. Specifically, among the markers (M), there is a marker (M2) indicating the stop position of the moving vehicle (A) and a marker (M1) set on the rear side of the direction of travel relative to the marker (M2), and a marker sensor (6) for detecting these two markers (M1, M2) is set on the moving vehicle (A). After the marker (M1) is detected by the marker sensor (6), the control device (9) set on the moving vehicle (A) starts deceleration control of the moving vehicle (A) at the time point when the distance from the moving vehicle (A) to the stop location becomes a set distance. Furthermore, when the marker (M2) is detected by the marker sensor (6), the control device (9) stops the moving vehicle (A). Summary of the Invention

[0004] As described above, in the control system of Patent Document 1, the movement of the moving vehicle is stopped when the marker sensor detects a marker located behind the stop position marker in the direction of travel, and then detects a stop position marker. That is, when the marker detection unit detects a stop warning marker and then detects a stop position marker, a movement stop process is executed to stop the movement of the goods transport vehicle. Furthermore, after the goods transport vehicle stops due to the movement stop process, the transfer of goods between the transport vehicle and the destination (in Patent Document 1, loading and unloading of goods at the station) is performed.

[0005] However, even if the transport vehicle has not reached the stop position, for various reasons, the marker detection unit may misdetect the stop position marker as if it were not one. For example, malfunctions of the marker detection unit, aging of the stop position marker, or noise such as interfering light could be the main causes of such misjudgments. If such a misjudgment occurs, and it is necessary to transfer items after the transport vehicle has stopped due to this misjudgment, it will be difficult to transfer the items properly because the transport vehicle has not reached the stop position.

[0006] Therefore, it is desirable to achieve a technology that can reduce the possibility of transferring items in situations where it is difficult to transfer items properly, even if the marker detection unit misdetects the stop position marker.

[0007] As one approach, the control system disclosed herein is a control system for controlling a goods transport vehicle that moves along a predetermined travel path to transport goods. It includes: a stop position indicator, positioned along the travel path corresponding to a stop location of the goods transport vehicle; and a higher-level control unit communicatively connected to the goods transport vehicle, outputting operating commands for the goods transport vehicle. The goods transport vehicle includes: a traveling section that moves along the travel path; a transfer section that holds the goods and transfers them between the goods and a transfer object disposed at the stop location; an indicator detection unit that detects the stop position indicator; and a control unit that controls the traveling section and the transfer section. The forward side of the travel direction of the goods transport vehicle moving along the travel path is designated as the downstream side, and the rear side of the travel direction is designated as the upstream side. The stop position indicator includes: a stop position indicator showing the stop location of the goods transport vehicle; and a stop warning indicator disposed on the upstream side relative to the stop position indicator. The upstream end of the stop warning sign is positioned at a predetermined warning distance relative to the stop position sign. When the stop warning sign is detected by the sign body detection unit, and then the stop position sign is detected by the sign body detection unit, the control unit performs a travel stop process to stop the travel of the traveling unit. After the travel of the traveling unit stops due to the travel stop process, the control unit performs a transfer process to transfer the item by the transfer unit. The item transport vehicle also includes a travel distance detection unit that detects the travel distance of the traveling unit. If, although the travel distance from the position where the stop warning sign is detected by the sign body detection unit is set to be less than a predetermined warning distance, the control unit detects the stop position sign by the sign body detection unit, and after the travel of the traveling unit stops due to the travel stop process, it performs an abnormality notification process to notify the upper control unit of the abnormality.

[0008] If the distance between the position of the stop warning sign detected by the sign body detection unit and the position of the stop position sign detected by the sign body detection unit (hereinafter referred to as the "object distance") is significantly shorter than the distance between the upstream end of the stop warning sign and the stop position sign, i.e., the warning distance, the sign body detection unit is highly likely to be falsely detecting the stop position sign. According to this structure, when the sign body detection unit detects the stop warning sign and then the stop position sign, the aforementioned object distance can be obtained based on the travel distance of the traveling unit from the position where the stop warning sign was detected. Then, if the obtained object distance is shorter than the warning distance to the point of being less than or equal to the determination distance, it can be determined that the detection of the stop position sign is false, and no transfer processing is performed after the traveling unit stops. Therefore, even if a false detection of the stop position sign occurs by the sign body detection unit, the possibility of transferring the item under conditions where it is difficult to transfer the item properly can be suppressed to a low level.

[0009] Furthermore, according to this structure, if no transfer processing is performed after the traveling part stops, as described above, the occurrence of an abnormality can be notified to the upper control unit that outputs the work command for the goods transport vehicle. Therefore, even if the indicator detection unit misdetects the stop position indicator, the state of the goods transport vehicle can be appropriately controlled by the upper control unit.

[0010] Alternatively, the control system disclosed herein is a control system for controlling a goods transport vehicle that moves along a predetermined travel path to transport goods. It includes a stop position marker disposed at a position in the travel path corresponding to a stop location of the goods transport vehicle. The goods transport vehicle comprises: a traveling unit that moves along the travel path; a transfer unit that holds the goods and transfers them between the goods and a transfer object disposed at the stop location; a marker detection unit that detects the stop position marker; and a control unit that controls the traveling unit and the transfer unit. The control unit of the part designates the front side of the travel direction of the transport vehicle traveling along the travel path as the downstream side and the rear side of the travel direction as the upstream side. The stop position marker includes: a stop position marker indicating the stop position of the transport vehicle, and a stop warning marker disposed on the upstream side relative to the stop position marker. The upstream end of the stop warning marker is disposed at a position that moves away from the stop position marker by a predetermined warning distance upstream. The control unit detects the stop position of the transport vehicle by the marker detection unit. After the stop warning sign is detected, if the item transport vehicle determines that it has reached the stop position sign based on the detection result of the sign body detection unit on the stop position sign, a travel stop process is executed to stop the travel of the moving part. After the travel of the moving part stops due to the travel stop process, a transfer process is executed to transfer the item by the transfer unit. The item transport vehicle also has a travel distance detection unit that detects the travel distance of the moving part. The control unit detects the stop warning sign from the sign body detection unit. If the travel distance from the location of the stop position marker is set to be less than the predetermined distance but the stop position marker is detected by the marker detection unit, the travel of the travel unit is not determined to have reached the location of the stop position marker and the travel unit continues to travel. If the travel distance from the location of the stop prediction marker detected by the marker detection unit exceeds the predetermined distance and the stop position marker is detected by the marker detection unit, the travel of the travel unit is determined to have reached the location of the stop position marker.

[0011] If the distance between the position of the stop warning sign detected by the sign body detection unit and the position of the stop position sign detected by the sign body detection unit (hereinafter referred to as the "object distance") is significantly shorter than the distance between the upstream end of the stop warning sign and the stop position sign, i.e., the warning distance, the sign body detection unit is highly likely to be falsely detecting the stop position sign. According to this structure, when the sign body detection unit detects the stop warning sign and then detects the stop position sign, the aforementioned object distance can be obtained based on the travel distance of the traveling unit from the position where the stop warning sign was detected. Then, if the obtained object distance is shorter than the warning distance to the point of being less than or equal to the determination distance, it can be determined that the detection of the stop position sign is false (in other words, it is not determined that the transport vehicle has reached the location of the stop position sign), and the traveling unit continues to travel without stopping. Therefore, even if the marking detection unit misdetects the stop position marking unit, the possibility of transferring the item under conditions where it is difficult to transfer the item properly can be suppressed to a low level.

[0012] Other features and advantages of the control system become clear from the following description of the embodiments illustrated with reference to the accompanying drawings. Attached Figure Description

[0013] Figure 1 It is a 3D view of a goods transport vehicle;

[0014] Figure 2 This is a side view of the goods transport vehicle;

[0015] Figure 3 It is an explanatory diagram of the control system;

[0016] Figure 4 This diagram shows three examples of timing for the detection of the stop position marker by the marker detection unit;

[0017] Figure 5 It is a control block diagram;

[0018] Figure 6 It is a control flow diagram;

[0019] Figure 7 It is a control flow diagram;

[0020] Figure 8 This is a control flowchart for other implementation methods. Detailed Implementation

[0021] The implementation of the control system is described with reference to the accompanying drawings. The control system 200 controls the transport vehicle 1 (see attached drawings) that moves along a predetermined path 40 to transport the items 2. Figure 1 , Figure 2The system is as follows. The transport cart 1 transports item 2 within the transport equipment 100. Item 2 is, for example, a FOUP (Front Opening Unified Pod) containing semiconductor wafers. In this embodiment, the transport cart 1 travels in one direction along the travel path 40. Here, as... Figures 1-3 As shown, the front side of the transport vehicle 1 traveling along the travel path 40 in the direction X is designated as the downstream side X2, and the rear side in the direction X is designated as the upstream side X1. The travel direction X is consistent with the length direction of the travel path 40 (the direction in which the travel path 40 extends). Furthermore, the direction orthogonal to both the travel direction X and the vertical direction Z is designated as the width direction Y.

[0022] The travel path 40 can be physically formed or virtually set. In this embodiment, the travel path 40 is physically formed using travel tracks 41. Specifically, the goods transport device 100 has travel tracks 41 arranged along the travel path 40 (here, a pair of travel tracks 41 arranged at intervals in the width direction Y), and the goods transport vehicle 1 travels along the travel tracks 41. Figure 2 As shown, the travel track 41 is suspended from the ceiling 3, and the travel path 40 is formed along the ceiling 3. That is, in this embodiment, the goods transport vehicle 1 is a ceiling transport vehicle that travels along the travel path 40 formed along the ceiling 3. Alternatively, the goods transport vehicle 1 can be a type of goods transport vehicle other than a ceiling transport vehicle. As an example of a goods transport vehicle other than a ceiling transport vehicle, a goods transport vehicle that travels along a travel path formed along the floor can be shown. In this case, the travel path can be formed by the travel track or can be virtually defined.

[0023] like Figure 1 and Figure 2 As shown, the goods transport vehicle 1 includes a traveling section 10 that travels along a travel path 40. The traveling section 10 includes wheels 11 and a travel drive unit 12 (e.g., an electric motor such as a servo motor) that rotates the wheels 11. The wheels 11 are driven to rotate by the travel drive unit 12, thereby causing the traveling section 10 to travel along the travel path 40. In this embodiment, the wheels 11 are configured to roll on the travel surface (here, the upper surface) of the travel track 41, and the traveling section 10 travels along the travel track 41 (here, a pair of travel tracks 41). In this example, the goods transport vehicle 1 includes a pair of traveling sections 10 arranged in the travel direction X.

[0024] like Figure 5As shown, the goods transport vehicle 1 includes a travel distance detection unit 32 that detects the travel distance ΔX of the traveling unit 10. In this embodiment, the travel distance detection unit 32 detects the travel distance ΔX based on the rotational speed (rotational speed) of the wheel 11. Specifically, the travel distance detection unit 32 derives the wheel movement amount based on the rotational speed of the wheel 11 and the diameter of the wheel 11, and detects the derived wheel movement amount as the travel distance ΔX. The travel distance detection unit 32 obtains the rotational speed of the wheel 11, for example, based on the detection result of an encoder provided on the output shaft of the traveling drive unit 12.

[0025] like Figure 2 As shown, the goods transport vehicle 1 includes a transfer unit 22, which holds the goods 2 and transfers the goods 2 between itself and a transfer destination 4. The transfer destination 4 is located at a station 50, which is set on the travel path 40 and becomes the destination of the goods transport vehicle 1. That is, the transfer destination 4 is located at the stopping point S of the goods transport vehicle 1 on the travel path 40 (refer to...). Figure 3 The transfer object 4 is, for example, the loading port of the processing device that processes the item 2, the storage rack for storing the item 2, or the entry / exit section (platform, conveyor belt, etc.) of the item 2 in the storage device for storing the item 2.

[0026] like Figure 2 As shown, the transfer unit 22 includes a holding part 21 for holding the article 2, and transfers the article 2 between the holding part 21 and the transfer object 4. In this embodiment, the transfer unit 22 is configured to move the holding part 21 between a reference position H1 and a transfer position H2. The reference position H1 is the position of the holding part 21 during the movement of the traveling unit 10. In this embodiment, the article transport vehicle 1 includes a main body 20 connected to the traveling unit 10, and the reference position H1 is the position that overlaps with the main body 20 in a top-bottom view (top view) along the vertical direction Z. Specifically, the reference position H1 is the position where the article 2 held in the holding part 21 is housed in the main body 20. In this example, the main body 20 is supported by the traveling unit 10 in a state where it is positioned at the lower side Z2 relative to the traveling unit 10, and the internal space of the main body 20 (the space for housing the article 2) is formed to be open at least towards the lower side Z2.

[0027] The transfer position H2 is the position of the holding part 21 during the transfer of the item 2 between the transfer unit 22 and the transfer target 4. The transfer position H2 is set according to the position of each transfer target 4. Figure 2As shown, in this embodiment, the transfer position H2 is located above the transfer object 4 at Z1 and overlaps with the transfer object 4 in the top view. In this embodiment, the transfer position H2 is located below the reference position H1 at Z2. Furthermore, in this embodiment, the transfer position H2 is located at a position overlapping with the main body 20 in the top view. That is, the transfer position H2 is positioned at the same location as the reference position H1 in the width direction Y.

[0028] In this embodiment, the transfer unit 22 moves the holding unit 21 between the reference position H1 and the transfer position H2 by raising and lowering the holding unit 21 relative to the traveling unit 10 (moving it in the vertical direction Z). Figure 2 As shown, in this embodiment, the transfer unit 22 raises and lowers the holding unit 21 while it is suspended and supported by the holding unit 21. Specifically, the holding unit 21 is connected to the front end of the transmission member 23 such as a belt or wire. The transfer unit 22 rotates the winding body (not shown) around the transmission member 23 by the driving force of the drive unit such as an electric motor to wind up or unwind the transmission member 23, thereby raising or lowering the holding unit 21.

[0029] Thus, in this embodiment, the transfer position H2 is positioned at the same location as the reference position H1 in the width direction Y, and the transfer unit 22 is configured to move the holding unit 21 between the reference position H1 and the transfer position H2 by moving the holding unit 21 relative to the traveling unit 10 in the vertical direction Z. Alternatively, the transfer position H2 can be configured to be positioned differently from the reference position H1 in the width direction Y, and the transfer unit 22 can move the holding unit 21 between the reference position H1 and the transfer position H2 by moving the holding unit 21 relative to the traveling unit 10 in the width direction Y, or by moving the holding unit 21 relative to the traveling unit 10 in both the vertical direction Z and the width direction Y.

[0030] When the transfer unit 22 transfers the article 2 between itself and the transfer target 4, it moves the holding unit 21 from the reference position H1 to the transfer position H2 corresponding to the transfer target 4. In this embodiment, the holding unit 21 holds the article 2 from the upper side Z1. Furthermore, the holding unit 21 is configured to be able to change the posture (at least one of position and orientation) of the holding unit 21 (specifically, the holding member provided by the holding unit 21) to a holding posture for holding the article 2 and a holding release posture for releasing the holding of the article 2.

[0031] When transferring an item 2 from the holding part 21 to the transfer target 4, the transfer part 22 moves the holding part 21, which holds the item 2, from the reference position H1 to the transfer position H2, then changes the posture of the holding part 21 from a holding posture to a holding release posture, and then moves the holding part 21 from the transfer position H2 to the reference position H1. Thus, the item 2 held in the holding part 21 is placed at the transfer target 4. Furthermore, when transferring an item 2 from the transfer target 4 to the holding part 21, the transfer part 22 moves the holding part 21, which does not hold the item 2, from the reference position H1 to the transfer position H2, then changes the posture of the holding part 21 from a holding release posture to a holding posture, and then moves the holding part 21 from the transfer position H2 to the reference position H1. Thus, the item 2 placed at the transfer target 4 is held by the holding part 21 and removed from the transfer target 4.

[0032] Unlike this structure, for example, it is also possible to configure the holding part 21 to hold the article 2 from the lower side Z2, and the transfer part 22 to raise and lower the holding part 21 at the transfer position H2, thereby transferring the article 2 between the holding part 21 and the transfer object 4. Specifically, it is possible to configure the transfer part 22 to raise the holding part 21 at the transfer position H2, thereby lifting the article 2 supported by the transfer object 4 using the holding part 21, transferring the article 2 from the transfer object 4 to the holding part 21, and then lowering the holding part 21 at the transfer position H2, thereby unloading the article 2 held by the holding part 21 to the transfer object 4.

[0033] like Figure 5 As shown, the goods transport vehicle 1 includes a control unit 30 that controls the traveling section 10 and the transfer section 22. The control unit 30 is configured to acquire information about the detection result of the traveling distance ΔX obtained by the traveling distance detection unit 32 described above, and information about the detection result of the stop position marker M obtained by the marker detection unit 31 described later. The control system 200 includes a higher-level control unit 60 communicatively connected to the goods transport vehicle 1, and the higher-level control unit 60 outputs operating commands for the goods transport vehicle 1. In this embodiment, a plurality of goods transport vehicles 1 are provided in the goods transport equipment 100, and the higher-level control unit 60 is communicatively connected to each of the plurality of goods transport vehicles 1, outputting operating commands for each of the plurality of goods transport vehicles 1. The control unit 30 controls the traveling section 10 and the transfer section 22 (specifically, the traveling section 10 and the transfer section 22 of the goods transport vehicle 1 to which the control unit 30 is provided) according to the operating commands from the higher-level control unit 60. The functions of the control unit 30 and the functions of the upper control unit 60 are realized through the cooperation of hardware such as an arithmetic processing device and a program executed on that hardware.

[0034] The work instructions for the goods transport vehicle 1 from the upper control unit 60 include a travel instruction, which specifies the destination. The control unit 30 controls the traveling unit 10 (specifically, the travel drive unit 12) according to the travel instruction from the upper control unit 60, so that it travels to the destination specified by the travel instruction. If the destination is a station 50 where a transfer object 4 is located, the control unit 30 controls the transfer unit 22 so that after the traveling unit 10 stops traveling at the destination, it transfers the goods 2 between the transfer unit 10 and the transfer object 4.

[0035] like Figure 3 As shown, the control system 200 includes a stop position marker M, which is positioned in the travel path 40 at a location corresponding to the stop point S of the transport vehicle 1. The stop position marker M is, for example, mounted on the travel track 41 (specifically, the lower surface of the travel track 41). The stop position marker M is used to stop the transport vehicle 1 at the stop point S when the stop point S where the stop position marker M is located is the destination of the transport vehicle 1. In this embodiment, the control system 200 also includes an information holding unit 7 positioned at the location corresponding to the stop point S. The information holding unit 7 holds address information indicating the location of the stop point S, and other information related to the stop point S.

[0036] The stop position indicator M has a stop position indicator M1 that indicates the stop position PS of the transport vehicle 1. The stop position PS is the designed stop position of the transport vehicle 1 at the stop location S where the stop position PS is set. The stop position PS is set according to the position of the transfer object 4 located at the stop location S. Specifically, the stop position PS is set at the position where the transfer unit 22 is positioned for transferring the item 2 between itself and the transfer object 4. As will be described later, when the stop position indicator M1 is detected by the indicator detection unit 31, the control unit 30 performs a travel stop process to stop the travel of the traveling unit 10. The position of the stop position indicator M1 is detected by the indicator detection unit 31 as the designed position (in Figure 3 In the case of the third position P3, the transport vehicle 1 stops at the stop position PS through the execution of the travel stop process.

[0037] The stop position indicator body M also includes a stop warning indicator M2 disposed on the upstream side X1 relative to the stop position indicator M1. For example... Figure 3 As shown, the end of the upstream side X1 of the stop warning indicator M2 is positioned at a predetermined warning distance D1 relative to the stop position indicator M1 (specifically, the end of the upstream side X1 of the stop position indicator M1) upstream of the stop position indicator M1. Figure 3In the example shown, the downstream end of the stop warning sign M2 is positioned at the same location in the travel direction X as the upstream end of the stop position sign M1. Here, the stop warning sign M2 is formed as a strip extending in the travel direction X. Furthermore, with... Figure 3 Different examples can also be configured such that the end of the downstream side X2 of the stop warning indicator M2 is separated from the end of the upstream side X1 of the stop position indicator M1 by the upstream side X1.

[0038] like Figure 5 As shown, the goods transport vehicle 1 includes a marker detection unit 31 that detects the stop position marker M1. The marker detection unit 31 detects both the stop position marker M1 and the stop warning marker M2. In this embodiment, the marker detection unit 31 detects both the stop position marker M1 and the stop warning marker M2 using a general-purpose sensor (such as a light sensor or a magnetic sensor). Alternatively, the marker detection unit 31 can be configured to include a sensor for detecting both the stop position marker M1 and the stop warning marker M2. Although details are omitted, the goods transport vehicle 1 includes a read information holding unit 7 (see reference 7). Figure 3 A reading device (not shown) that holds the information. If the information holder 7 is a barcode, the reading device is a barcode reader.

[0039] In this embodiment, the stop position marker M is composed of a light-reflecting component such as a light-reflecting strip, and the marker detection unit 31 includes a light sensor for detecting the stop position marker M (specifically, detecting the presence of the stop position marker M). This light sensor is a reflective type, detecting the stop position marker M by projecting detection light and receiving the reflected light (reflected light from the object being detected). The stop position marker M is configured such that the reflectivity of the detection light is higher than that of the component on which the stop position marker M is mounted (e.g., the travel track 41). Therefore, when the detection intensity of the reflected light obtained by the marker detection unit 31 changes from a value lower than a predetermined threshold to a value higher than that threshold, the stop position marker M is detected.

[0040] The stop position marker M1 and the stop warning marker M2 are configured such that the reflectivity of the detection light is different from each other. The marker detection unit 31 detects the stop position marker M1 and the stop warning marker M2 separately by measuring the intensity of the reflected light. In this embodiment, the stop position marker M1 is configured such that the reflectivity of the detection light is higher than that of the stop warning marker M2. Therefore, the stop warning marker M2 is detected when the intensity of the reflected light detected by the marker detection unit 31 changes from a value lower than a predetermined first threshold T1 to a value higher than the first threshold T1. Furthermore, the stop position marker M1 is detected when the intensity of the reflected light detected by the marker detection unit 31 changes from a value lower than a predetermined second threshold T2 to a value higher than the second threshold T2. The second threshold T2 is set to a value greater than the first threshold T1.

[0041] exist Figure 3 The diagram shows the change (ideal change) in the intensity of the reflected light detected by the marker detection unit 31 relative to the position of the transport vehicle 1, without any detection error from the marker detection unit 31. (As shown) Figure 3 As shown, as the transport vehicle 1 moves downstream X2, the detection intensity of the reflected light obtained by the marker detection unit 31 increases as the transport vehicle 1 reaches the first position P1 (the position where the end of the upstream X1 of the stop warning marker M2 is located), thereby detecting the stop warning marker M2. Then, before the transport vehicle 1 reaches the third position P3 (the position where the end of the upstream X1 of the stop position marker M1 is located) downstream X2 of the first position P1, the detection intensity of the reflected light obtained by the marker detection unit 31 is maintained at the increased intensity. The aforementioned first threshold T1 is set to a value lower than the detection intensity of the reflected light obtained by the marker detection unit 31 when the marker detection unit 31 receives the reflected light from the detection light of the stop warning marker M2.

[0042] The detection intensity of the reflected light obtained by the marker detection unit 31 increases as the transport vehicle 1 reaches the third position P3, thereby detecting the stop position marker M1. Then, before the transport vehicle 1 reaches the fourth position P4 (the position where the end of the downstream side X2 of the stop position marker M1 is located) downstream of the third position P3, the detection intensity of the reflected light obtained by the marker detection unit 31 is maintained at the increased intensity. The aforementioned second threshold T2 is set to a value that is higher than the detection intensity of the reflected light obtained by the marker detection unit 31 when the marker detection unit 31 receives the reflected light from the detection light of the stop warning marker M2, and lower than the detection intensity of the reflected light obtained by the marker detection unit 31 when the marker detection unit 31 receives the reflected light from the detection light of the stop position marker M1.

[0043] After the sign body detection unit 31 detects the stop warning sign M2, and then detects the stop position sign M1, the control unit 30 executes a movement stop process to stop the movement of the traveling unit 10. After the traveling unit 10 stops due to the movement stop process, it executes a transfer process to transfer the item 2 to the transfer unit 2. Furthermore, the stop position sign M1 and the stop warning sign M2 mentioned here are the stop position sign M and the stop warning sign M2 provided on the stop position sign M located at the stop location S, which is the destination.

[0044] In this embodiment, when the marker detection unit 31 detects the stop warning marker M2, the control unit 30 controls the travel speed of the traveling unit 10 so that the travel speed of the traveling unit 10 is reduced to a creep speed (a speed for slow travel) before the transport vehicle 1 reaches the third position P3. Then, when the marker detection unit 31 detects the stop position marker M1, the control unit 30 reduces the travel speed of the traveling unit 10 to zero, stopping the travel of the traveling unit 10. Furthermore, the deceleration of the traveling speed of the traveling unit 10 (e.g., deceleration from a stable travel speed) can be configured to begin after the marker detection unit 31 detects the stop warning marker M2 (i.e., at the first position P1), or it can be configured to begin before the marker detection unit 31 detects the stop warning marker M2 (i.e., at the position X1 upstream of the first position P1).

[0045] However, even though the transport vehicle 1 has not reached the third position P3 (the position where the end of the upstream side X1 of the stop position indicator M1 is located), for some reason, it is still possible for the indicator body detection unit 31 to falsely detect the stop position indicator M1 as if it were not the stop position indicator M1. Although it is also possible for the indicator body detection unit 31 to falsely detect the stop warning indicator M2, it is less likely to occur for the indicator body detection unit 31 to falsely detect the stop warning indicator M2 as if it were a component (e.g., the travel track 41) on which the stop position indicator M is mounted, by using, for example, a polarizing filter. Therefore, the possibility of the indicator body detection unit 31 falsely detecting the stop position indicator M1 is higher than that of the indicator body detection unit 31 falsely detecting the stop warning indicator M2.

[0046] In view of the above, if the travel distance ΔX from the position of the stop warning marker M2 detected by the marker detection unit 31 is less than or equal to the determination distance D2 (which is set to be less than the warning distance D1), but the marker detection unit 31 detects the stop position marker M1, then after the travel unit 10 stops due to the travel stop processing, the control unit 30 performs an exception notification process to notify the upper control unit 60 of the occurrence of the exception, instead of the transfer processing. That is, if the travel distance ΔX from the position of the stop warning marker M2 detected by the marker detection unit 31 to the position of the stop position marker M1 detected by the marker detection unit 31 is less than or equal to the determination distance D2, then after the travel unit 10 stops due to the travel stop processing, the control unit 30 performs an exception notification process instead of the transfer processing. On the other hand, if the travel distance ΔX from the position of the stop warning marker M2 detected by the marker detection unit 31 exceeds the determination distance D2, and the marker detection unit 31 detects the stop position marker M1, the control unit 30 performs a transfer process after the travel unit 10 stops due to the travel stop processing. That is, if the travel distance ΔX from the position of the stop warning marker M2 detected by the marker detection unit 31 to the position of the stop position marker M1 detected by the marker detection unit 31 is greater than the determination distance D2, the control unit 30 performs a transfer process after the travel unit 10 stops due to the travel stop processing. By performing this control, even assuming a false detection of the stop position marker M1 by the marker detection unit 31, the possibility of transferring the item 2 under conditions where it is difficult to transfer the item 2 properly can be suppressed to a low level.

[0047] Reference Figure 6 Here is an example illustrating the operation sequence of the control processing of the control unit 30. After the marker detection unit 31 detects the stop warning marker M2 (step #01: Yes), and then the marker detection unit 31 detects the stop position marker M1 (step #02: Yes), the control unit 30 executes a movement stop process (step #03) to stop the movement of the traveling unit 10. Then, if the travel distance ΔX from the position where the marker detection unit 31 detects the stop warning marker M2 to the position where the marker detection unit 31 detects the stop position marker M1 is not less than the determination distance D2 (step #04: No), the control unit 30 executes a transfer process (step #05); if the travel distance ΔX is less than the determination distance D2 (step #04: Yes), it executes an error notification process (step #06).

[0048] exist Figure 3 and Figure 4In the example shown, the second position P2 is a position located X2 downstream of the first position P1 (the position where the end of the upstream side X1 of the stop warning indicator M2 is configured) and a determination distance D2 away. Then, Figure 4 (a) and Figure 4 (b) shows a situation where the travel distance ΔX (hereinafter referred to as "the travel distance ΔX of the object") from the position of the stop warning sign M2 detected by the sign body detection unit 31 to the position of the stop position sign M1 detected by the sign body detection unit 31 is greater than the determination distance D2. Figure 4 of (a) Figure 4 In the situation shown in (b), the control unit 30 performs a transfer process after the movement of the movement unit 10 stops due to the movement stop processing. Not only in situations such as... Figure 4 As shown in (a), when the travel distance ΔX of the object is consistent with the predicted distance D1, and by configuring it as follows: Figure 4 When the travel distance ΔX of the object, as shown in (b), is the size between the determination distance D2 and the prediction distance D1, a transfer process is also performed to absorb the detection error of the travel distance detection unit 32 on the travel distance ΔX. That is, the difference between the prediction distance D1 and the determination distance D2 is set based on the detection error of the travel distance detection unit 32 on the travel distance ΔX. Figure 3 and Figure 4 In the example shown, the decision distance D2 is set such that the difference between the prediction distance D1 and the decision distance D2 is less than the decision distance D2.

[0049] Figure 4 (c) shows a situation where the travel distance ΔX of the object being detected is less than or equal to the determination distance D2 due to a false detection of the stop position marker M1 by the marker detection unit 31. Figure 4 In the situation shown in (c), after the movement of the moving unit 10 stops due to the movement stop processing, the control unit 30 performs abnormal notification processing instead of transfer processing. Preferably, the travel distance ΔX from the position of the stop warning sign M2 detected by the sign body detection unit 31 is within the range of the judgment distance D2 or less. Figure 3 and Figure 4 The range between the first position P1 and the second position P2 is set in a way that matches the range of the item 2 between the transfer object 4 and the transfer target 2, which cannot be transferred by the transfer unit 22.

[0050] To further reduce the possibility of transferring item 2 under conditions where it is difficult to transfer it properly, it is preferable that the control unit 30 is configured to perform the transfer process after the marker detection unit 31 detects the stop position marker M1 and the state of detecting the stop position marker M1 continues for a set time or more. In this case, even if the marker detection unit 30 detects the stop position marker M1 after the travel distance ΔX of the object exceeds the determination distance D2, and the state of detecting the stop position marker M1 does not continue for a set time or more, the control unit 30 will perform an exception notification process instead of the transfer process after the travel stop process causes the travel unit 10 to stop.

[0051] When the control unit 30 performs an anomaly notification process to notify the upper control unit 60 of an anomaly, information about at least one of the transport vehicle 1 equipped with the control unit 30 and the stop position marker M involved in the anomaly (in this embodiment, information about both) is sent from the transport vehicle 1 to the upper control unit 60. Here, the stop position marker M involved in the anomaly is a stop position marker M that, although the travel distance ΔX of the object being detected is less than or equal to the determination distance D2, is detected by the marker detection unit 31 as a stop position marker M1. The information about the transport vehicle 1 and the stop position marker M can be information that directly determines them (e.g., identification information of the transport vehicle 1, identification information of the stop position marker M) or information that indirectly determines them (e.g., information about the stop location S where the stop position marker M is located, which is information about the stop position marker M).

[0052] In this embodiment, when the upper-level control unit 60 receives a notification of an anomaly from the control unit 30, it stores the anomaly information in the storage device 61. The anomaly information includes information about at least one of the transport vehicle 1 equipped with the control unit 30 and the stop position marker M related to the anomaly (in this embodiment, information about both). The storage device 61 includes, for example, a flash memory or a hard disk storage medium. Figure 5 In the example shown, the storage device 61 is located in the host control unit 60. Furthermore, the host control unit 60 can also be configured not to store exception information in the storage device 61.

[0053] In this embodiment, when the upper control unit 60 receives a notification of an anomaly from the control unit 30, it outputs a travel command to the transport vehicle 1 equipped with the control unit 30, specifying the stop location S, where the stop location marker M related to the anomaly is located, as the destination. Then, the control unit 30 receives the re-output travel command and resumes travel using the travel unit 10. It can be configured such that, upon resuming travel using the travel unit 10, the control unit 30, for example, begins determining whether the marker detection unit 31 detects the stop location marker M1 in conjunction with the resumption of travel using the travel unit 10. In this case, before the transport vehicle 1 exits from the stop location S where the stop location marker M is located, the marker detection unit 31 detects the stop location marker M1, and accordingly performs a travel stop process. Furthermore, after the travel unit 10 stops due to the travel stop process, a transfer process or an anomaly notification process is performed.

[0054] Unlike the above structure, the control unit 30 can also be configured to determine whether the stop position indicator M1 is detected by the indicator detection unit 31 without matching the restart of the travel unit 10. For example, it can also be configured such that after restarting the travel unit 10, the control unit 30 causes the transport vehicle 1 to exit from the stop point S where the stop position indicator M related to the abnormality is located to the downstream side X2, and then travels from the upstream side X1 to the same stop point S. For example, the control unit 30 can cause the transport vehicle 1 to travel from the upstream side X1 to the same stop point S by causing the transport vehicle 1 to travel in a manner that makes one loop around the circular path included in the travel path 40. In this case, as the transport vehicle 1 reaches the same stop point S, the indicator detection unit 31 detects the stop warning indicator M2, and then the indicator detection unit 31 detects the stop position indicator M1. Then, a travel stop process is performed based on the detection of the stop position indicator M1 by the indicator detection unit 31, and after the travel of the travel unit 10 stops due to the travel stop process, a transfer process or an error notification process is performed.

[0055] As described above, in this embodiment, when the upper control unit 60 receives a notification of an anomaly from the control unit 30, it again outputs a travel command to the transport vehicle 1 equipped with the control unit 30, specifying the stop location S, where the stop position marker M related to the anomaly is located, as the destination. Furthermore, in this embodiment, if the number of anomaly notifications from the same transport vehicle 1 regarding the same stop position marker M exceeds a predetermined number, the upper control unit 60 does not output the travel command again, but instead issues an anomaly report using the display device 5 or the sound output device 6. Both anomaly reports using the display device 5 and anomaly reports using the sound output device 6 may be performed. The predetermined number is, for example, set to 2 times. Figure 5 As shown, in this embodiment, the control system 200 includes a display device 5 and a sound output device 6. Anomalies are reported via a screen display (display of an anomaly report screen) using the display device 5, and anomalies are reported via sound output (output of an anomaly report sound) using the sound output device 6.

[0056] Reference Figure 7 Here is an example illustrating the operation sequence of the control processing of the upper control unit 60. When the upper control unit 60 receives a notification of an anomaly from the control unit 30 (step #10: Yes), it performs an anomaly information storage process (step #11) to store the anomaly information in the storage device 61. Then, if the number of anomaly notifications from the same transport vehicle 1 regarding the same stop position marker M is not more than a predetermined number (step #12: No), the upper control unit 60 performs a travel command re-output process (step #13). This process re-outputs a travel command to the transport vehicle 1 equipped with the control unit 30 that notified of the anomaly, setting the stop location S where the stop position marker M involved in the anomaly is located as the destination. On the other hand, if the number of anomaly notifications from the same transport vehicle 1 regarding the same stop position marker M becomes more than a predetermined number (step #12: Yes), the upper control unit 60 performs an anomaly notification process (step #14), which sends an anomaly notification using the display device 5 or the sound output device 6.

[0057] The technical features of the control system 200 for controlling the goods transport vehicle 1 disclosed in this specification can also be applied to the control method for the goods transport vehicle 1, which is also disclosed in this specification. In this embodiment, the control method includes a control unit 30 executing... Figure 6 The process steps (each step) shown are executed by the upper control unit 60. Figure 7 The procedures for each processing step are shown.

[0058] [Other Implementation Methods]

[0059] Next, other implementations of the control system will be described.

[0060] (1) In the above embodiment, the following structure was described as an example: when the number of notifications of abnormal occurrences from the same goods transport vehicle 1 for the same stop position marker M becomes a predetermined number or more, the upper control unit 60 does not re-output the travel command, but instead issues an abnormality notification using the display device 5 or the sound output device 6. However, this disclosure is not limited to this structure. Instead of the number of notifications of abnormal occurrences from the same goods transport vehicle 1 for the same stop position marker M becoming a predetermined number or more, the condition for the upper control unit 60 to issue an abnormality notification may also be that the number of notifications of abnormal occurrences from the same goods transport vehicle 1 becomes a predetermined number or more, or that the number of notifications of abnormal occurrences for the same stop position marker M becomes a predetermined number or more. Furthermore, it is also possible for the upper control unit 60 to only re-output the travel command or issue an abnormality notification, regardless of the number of notifications of abnormal occurrences.

[0061] (2) In the above embodiment, the following structure is used as an example: When the upper control unit 60 receives a notification of an anomaly from the control unit 30, it outputs a travel command to the transport vehicle 1 equipped with the control unit 30 again, specifying the stop location S, which is marked with the stop location marker M related to the anomaly, as the destination. However, this disclosure is not limited to this structure. It is also possible for the upper control unit 60 to output a travel command specifying a stop location S, which is different from the stop location S marked with the stop location marker M related to the anomaly, as the destination, instead of outputting the travel command specifying the stop location S as the destination again.

[0062] (3) In the above embodiment, the following structure was described as an example: When the upper control unit 60 receives a notification of an anomaly from the control unit 30, it outputs a travel command to the transport vehicle 1 equipped with the control unit 30, specifying the stop location S, where the stop location marker M involved in the anomaly is located, as the destination. However, this disclosure is not limited to this structure. It is also possible to configure the transport vehicle 1 to resume travel of the transport vehicle 10 after the travel vehicle 10 stops due to the travel stop processing, even if the travel distance ΔX from the location of the stop warning marker M2 detected by the marker detection unit 31 is less than or equal to the determination distance D2, but the stop location marker M1 is detected by the marker detection unit 31. In this case, the control unit 30 may also be configured not to perform the anomaly notification processing.

[0063] (4) In the above embodiment, the following structure was described as an example: when the number of notifications from the same goods transport vehicle 1 regarding the same stop position marker M becomes a set number or more, the upper control unit 60 does not output the travel command again, but instead issues an abnormality notification using the display device 5 or the sound output device 6. However, this disclosure is not limited to this structure, and it is also possible for the control unit 30 to issue an abnormality notification using the display unit 33 or the sound output unit 34 when the travel distance ΔX from the position of the stop warning marker M2 detected by the marker detection unit 31 is less than the determination distance D2, but the number of times the stop position marker M1 is detected by the marker detection unit 31 (hereinafter referred to as the "object number") becomes a set number or more. It is also possible to issue both abnormality notifications using the display unit 33 and abnormality notifications using the sound output unit 34. Furthermore, the set number may be the same as or different from the set number involved in the abnormality notification using the upper control unit 60 in the above embodiment. Furthermore, the number of objects can be, for example, the total value for each stop position marker M, or the sum of the total values ​​for all stop position markers M (in other words, the total value for each item transport vehicle 1). Figure 5 In the example shown, the display unit 33 and the sound output unit 34 are installed on the goods transport vehicle 1. The abnormality notification of the display unit 33 is performed by displaying the screen (displaying the abnormality notification screen), and the abnormality notification of the sound output unit 34 is performed by outputting the sound (outputting the abnormality notification sound).

[0064] (5) In the above embodiment, the following structure is used as an example: When the control unit 30 detects the stop warning sign M2 by the sign body detection unit 31, and then detects the stop position sign M1 by the sign body detection unit 31, regardless of whether the travel distance ΔX of the target (specifically, the travel distance ΔX from the position where the stop warning sign M2 is detected by the sign body detection unit 31 to the position where the stop position sign M1 is detected by the sign body detection unit 31) is less than or equal to the determination distance D2, the travel stop process is performed. However, this disclosure is not limited to this structure, and the following structure can also be adopted.

[0065] After the stop warning sign M2 is detected by the sign body detection unit 31, the control unit 30 determines, based on the detection result of the sign body detection unit 31 on the stop position sign M1, that the goods transport vehicle 1 has reached the setting position of the stop position sign M1 (in Figure 3 and Figure 4 In the example shown, in the case of the third position (P3), a travel stop process is executed to stop the travel of the traveling unit 10. After the travel of the traveling unit 10 stops due to the travel stop process, a transfer process is executed to transfer the item 2 to the transfer unit 2. Moreover, if the travel distance ΔX from the position of the stop warning sign M2 detected by the sign body detection unit 31 is less than or equal to the determination distance D2, but the stop position sign M1 is detected by the sign body detection unit 31, the control unit 30 does not determine that the item transport vehicle 1 has reached the setting position of the stop position sign M1, and continues the travel of the traveling unit 10. Therefore, in Figure 4 In the situation shown in (c), it is not determined that the transport vehicle 1 has reached the setting position of the stop position indicator M1, and the travel unit 10 continues to travel. On the other hand, if the travel distance ΔX from the position of the stop warning indicator M2 detected by the indicator detection unit 31 exceeds the determination distance D2, and the stop position indicator M1 is detected by the indicator detection unit 31, the control unit 30 determines that the transport vehicle 1 has reached the setting position of the stop position indicator M1. Therefore, in Figure 4 of (a) Figure 4 In the case shown in (b), it is determined that the transport vehicle 1 has reached the location of the stop position indicator M1, and the travel stop process and transfer process are executed in sequence.

[0066] Reference Figure 8Here is an example of the operation sequence of the control processing of the control unit 30 in this embodiment. After the marker detection unit 31 detects the stop warning marker M2 (step #20: Yes), the control unit 30 determines whether the transport vehicle 1 has reached the setting position of the stop position marker M1 based on the detection result of the marker detection unit 31 on the stop position marker M1. Specifically, if the marker detection unit 31 detects the stop position marker M1 (step #21: Yes), the control unit 30 determines whether the travel distance ΔX of the object is less than or equal to the determination distance D2 (step #22). Then, if the travel distance ΔX of the object is less than or equal to the determination distance D2 (step #22: Yes), the control unit 30 does not determine that the transport vehicle 1 has reached the setting position of the stop position marker M1, and continues the movement of the traveling unit 10. On the other hand, if the travel distance ΔX of the object is not less than or equal to the determination distance D2 (step #22: No), the control unit 30 determines that the transport vehicle 1 has reached the setting position of the stop position indicator M1 and executes the travel stop processing (step #23). After the travel of the transport vehicle 10 stops due to the travel stop processing, the transfer processing is executed (step #24). In this embodiment, the control method of the transport vehicle 1 includes the control unit 30 executing... Figure 8 The procedures for each processing step are shown.

[0067] (6) Furthermore, as long as no contradiction arises, the structures disclosed in the above embodiments can also be used in combination with structures disclosed in other embodiments (including combinations of embodiments described as other embodiments with each other). Regarding other structures, the embodiments disclosed in this specification are merely illustrative in all respects. Therefore, various changes can be appropriately made without departing from the spirit of this disclosure.

[0068] [Summary of the above embodiments]

[0069] The following is a summary of the control system described above.

[0070] A control system for controlling a goods transport vehicle that moves along a predetermined travel path to transport goods includes: a stop position indicator disposed at a position in the travel path corresponding to a stop location of the goods transport vehicle; and a higher-level control unit communicatively connected to the goods transport vehicle and outputting work commands for the goods transport vehicle. The goods transport vehicle includes: a traveling section that moves along the travel path; a transfer section that holds the goods and transfers them between the goods and a transfer object disposed at the stop location; an indicator detection section that detects the stop position indicator; and a control section that controls the traveling section and the transfer section. The forward side of the travel direction of the goods transport vehicle moving along the travel path is designated as the downstream side, and the rear side of the travel direction is designated as the upstream side. The stop position indicator includes: a stop position indicator showing the stop location of the goods transport vehicle; and a stop warning indicator disposed on the upstream side relative to the stop position indicator. The upstream end is positioned at a predetermined warning distance relative to the stop position indicator. When the stop warning indicator is detected by the indicator detection unit, and then the stop position indicator is detected by the indicator detection unit, the control unit performs a travel stop process to stop the travel of the traveling unit. After the travel of the traveling unit stops due to the travel stop process, the control unit performs a transfer process to transfer the item by the transfer unit. The item transport vehicle also includes a travel distance detection unit for detecting the travel distance of the traveling unit. Even if the travel distance from the position where the stop warning indicator is detected by the indicator detection unit is set to be less than the warning distance, but the stop position indicator is detected by the indicator detection unit, after the travel of the traveling unit stops due to the travel stop process, the control unit performs an abnormality notification process to notify the upper control unit of the abnormality.

[0071] If the distance between the position of the stop warning sign detected by the sign body detection unit and the position of the stop position sign detected by the sign body detection unit (hereinafter referred to as the "object distance") is significantly shorter than the distance between the upstream end of the stop warning sign and the stop position sign, i.e., the warning distance, the sign body detection unit is highly likely to be falsely detecting the stop position sign. According to this structure, when the sign body detection unit detects the stop warning sign and then the stop position sign, the aforementioned object distance can be obtained based on the travel distance of the traveling unit from the position where the stop warning sign was detected. Then, if the obtained object distance is shorter than the warning distance to the point of being less than or equal to the determination distance, it can be determined that the detection of the stop position sign is false, and no transfer processing is performed after the traveling unit stops. Therefore, even if a false detection of the stop position sign occurs by the sign body detection unit, the possibility of transferring the item under conditions where it is difficult to transfer the item properly can be suppressed to a low level.

[0072] Furthermore, according to this structure, if no transfer processing is performed after the traveling part stops, as described above, the occurrence of an abnormality can be notified to the upper control unit that outputs the work command for the goods transport vehicle. Therefore, even if the indicator detection unit misdetects the stop position indicator, the state of the goods transport vehicle can be appropriately controlled by the upper control unit.

[0073] Preferably, when the upper control unit receives a notification of the occurrence of the abnormality from the control unit, it outputs a travel command to the transport vehicle equipped with the control unit again, setting the stop location marked with the stop position indicator related to the occurrence of the abnormality as the destination. The control unit receives the re-output travel command and resumes travel using the travel unit.

[0074] According to this structure, even if the movement of the traveling unit stops due to a misdetection of the stop position indicator by the indicator detection unit, the movement of the traveling unit can be restarted so that the goods transport vehicle stops at the stop position corresponding to the intended transfer object. Therefore, even in cases where the misdetection of the stop position indicator by the indicator detection unit is accidental, the goods transport vehicle can perform the transfer of goods between the intended transfer object and the intended transfer object.

[0075] In a structure where, as described above, the upper control unit re-outputs the travel command to the transport vehicle equipped with the control unit upon receiving notification of the occurrence of the abnormality from the control unit, it is preferable that, if the number of notifications of the occurrence of the abnormality from the same transport vehicle for the same stop position marker becomes more than a set number, the upper control unit does not re-output the travel command, but instead issues an abnormality notification using a display device or a sound output device.

[0076] When notifications of abnormalities occurring repeatedly from the same transport vehicle for the same stop position marker are received, there is a possibility that the marker detection unit's misdetection of the stop position marker is not accidental, but rather indicates a problem with either the marker detection unit or the stop position marker itself. According to this structure, when the number of such abnormality notifications exceeds a predetermined number, an abnormality report is issued using a display device or an audio output device. Therefore, in cases where a problem exists in either the marker detection unit or the stop position marker, it can prompt the operator to confirm the issue.

[0077] In the control systems of the above-described structures, it is preferable that when the upper control unit receives a notification of the occurrence of the abnormality from the control unit, it stores the abnormality information in a storage device. The abnormality information includes information about at least one of the transport vehicle equipped with the control unit and the stop position marker involved in the abnormality.

[0078] According to this structure, by storing the information of the abnormality occurrence in the storage device, it is possible to retain the history of the abnormality occurrence. Therefore, if a problem occurs in the marker detection unit or the stop position marker, it is easy to identify the item transport vehicle equipped with the marker detection unit that has the problem or the stop position marker that has the problem.

[0079] A control system for controlling a goods transport vehicle that moves along a predetermined travel path, comprising a stop position marker disposed at a position in the travel path corresponding to a stop location of the goods transport vehicle, the goods transport vehicle comprising: a traveling unit that moves along the travel path, a transfer unit that holds the goods and transfers them between the goods and a transfer object disposed at the stop location, a marker detection unit that detects the stop position marker, and a control unit that controls the traveling unit and the transfer unit. The forward side of the travel direction of the transport vehicle traveling along the described path is designated as the downstream side, and the rear side of the travel direction is designated as the upstream side. The stop position marker includes: a stop position marker indicating the stop position of the transport vehicle, and a stop warning marker disposed on the upstream side relative to the stop position marker. The upstream end of the stop warning marker is disposed at a position that moves away from the stop position marker by a predetermined warning distance upstream. The control unit detects the stop warning marker by the marker detection unit. Subsequently, based on the detection result of the marker detection unit on the stop position marker, if it is determined that the item transport vehicle has reached the setting position of the stop position marker, a travel stop process is executed to stop the travel of the traveling unit. After the traveling unit stops due to the travel stop process, a transfer process is executed to transfer the item by the transfer unit. The item transport vehicle also has a travel distance detection unit that detects the travel distance of the traveling unit. The control unit detects the position of the stop warning marker from the marker detection unit. If the travel distance is set to be less than the predetermined distance but the stop position marker is detected by the marker detection unit, the traveler will not be determined to have reached the position of the stop position marker and will continue to travel. If the travel distance from the position where the stop warning marker is detected by the marker detection unit exceeds the predetermined distance, and the stop position marker is detected by the marker detection unit, the traveler will be determined to have reached the position of the stop position marker.

[0080] If the distance between the position of the stop warning sign detected by the sign body detection unit and the position of the stop position sign detected by the sign body detection unit (hereinafter referred to as the "object distance") is significantly shorter than the distance between the upstream end of the stop warning sign and the stop position sign, i.e., the warning distance, the sign body detection unit is highly likely to be falsely detecting the stop position sign. According to this structure, when the sign body detection unit detects the stop warning sign and then detects the stop position sign, the aforementioned object distance can be obtained based on the travel distance of the traveling unit from the position where the stop warning sign was detected. Then, if the obtained object distance is shorter than the warning distance to the point of being less than or equal to the determination distance, it can be determined that the detection of the stop position sign is false (in other words, it is not determined that the transport vehicle has reached the location of the stop position sign), and the traveling unit continues to travel without stopping. Therefore, even if the marking detection unit misdetects the stop position marking unit, the possibility of transferring the item under conditions where it is difficult to transfer the item properly can be suppressed to a low level.

[0081] In the control systems of the above-described structures, it is preferable that the control unit provides an abnormality notification using the display unit or the sound output unit when the travel distance from the position of the stop warning sign detected by the sign body detection unit is less than or equal to the determination distance, but the number of times the stop position sign is detected by the sign body detection unit becomes more than or equal to a set number.

[0082] Even if the distance traveled from the position of the stop warning sign detected by the sign body detection unit is less than the judgment distance, but the stop position sign is repeatedly detected by the sign body detection unit, the false detection of the stop position sign by the sign body detection unit is not accidental, and there may be a problem in the sign body detection unit or the stop position sign. According to this structure, even if the distance traveled from the position of the stop warning sign detected by the sign body detection unit is less than the judgment distance, but the number of times the stop position sign is detected by the sign body detection unit is more than a set number, an abnormality report is made by the display unit or the sound output unit. Therefore, in cases where there may be a problem in the sign body detection unit or the stop position sign, the operator can be prompted to check.

[0083] Furthermore, it is preferable that the range from the position of the stop warning sign detected by the sign body detection unit to the range of the travel distance being less than the determination distance is set in a manner that matches the range in which the transfer of the item between the transfer unit and the transfer object cannot be performed.

[0084] According to this structure, the determination distance can be set appropriately to reduce the possibility of transferring items when it is difficult to transfer items properly.

[0085] Furthermore, preferably, after the marker detection unit detects the stop position marker, the control unit performs the transfer process if the state of detecting the stop position marker has lasted for a set time or more.

[0086] Even if the stop position marker is detected by the marker detection unit, if the detection of the stop position marker does not continue, the detection of the stop position marker is likely to be a false detection. According to this structure, the transfer process can be performed under the condition that the stop position marker is continuously detected by the marker detection unit, thus easily avoiding the transfer of items when it is difficult to transfer them properly.

[0087] The control system disclosed herein only needs to achieve at least one of the aforementioned effects.

[0088] Explanation of reference numerals in the attached figures

[0089] 1: Goods transport vehicle

[0090] 2: Items

[0091] 4: Location of the object to be migrated

[0092] 5: Display device

[0093] 6: Sound output device

[0094] 10: Marching Section

[0095] 22: Transfer section

[0096] 30: Control Department

[0097] 31: Marker Inspection Department

[0098] 32: Travel Distance Detection Department

[0099] 33: Display Section

[0100] 34: Sound Output Section

[0101] 40: Route

[0102] 60: Upper control unit

[0103] 61: Storage device

[0104] 200: Control System

[0105] D1: Forecast Distance

[0106] D2: Determine Distance

[0107] M: Stop position marker

[0108] M1: Stop position indicator

[0109] M2: Stop Warning Signage

[0110] PS: Stop position

[0111] S: Stop location

[0112] X: Direction of travel

[0113] X1: Upstream side

[0114] X2: Downstream side

[0115] ΔX: Distance traveled.

Claims

1. A control system for controlling a goods transport vehicle that travels along a predetermined path to transport goods, characterized in that, have: A stop position marker is placed at a location on the travel path corresponding to the stopping point of the goods transport vehicle; and The host control unit is communicatively connected to the transport vehicle and outputs operating commands for the transport vehicle. The transport vehicle includes: a traveling unit that travels along the travel path; a transfer unit that holds the items and transfers the items between them and a transfer object disposed at the stop location; a marker detection unit that detects the stop position marker; and a control unit that controls the traveling unit and the transfer unit. The front side of the transport vehicle traveling along the travel path is designated as the downstream side, and the rear side of the travel direction is designated as the upstream side. The stop position indicator includes: a stop position indicator showing the stop position of the goods transport vehicle, and a stop warning indicator disposed on the upstream side relative to the stop position indicator. The upstream end of the stop warning indicator is positioned at a predetermined warning distance relative to the stop position indicator, moving upstream from the stop position indicator. When the control unit detects the stop warning sign after the sign body detection unit detects the stop position sign, it executes a movement stop process to stop the movement of the traveling unit. After the movement of the traveling unit stops due to the movement stop process, it executes a transfer process to cause the transfer unit to transfer the item. The transport vehicle also has a travel distance detection unit for detecting the travel distance of the traveling unit. Even if the travel distance from the position of the stop warning sign detected by the sign body detection unit is set to be less than the judgment distance of the warning distance, but the stop position sign is detected by the sign body detection unit, the control unit, after the travel of the travel unit stops due to the travel stop processing, performs an abnormal notification process to notify the upper control unit of the abnormality occurrence instead of the transfer processing.

2. The control system according to claim 1, wherein, Upon receiving notification of the anomaly from the control unit, the upper-level control unit outputs a travel command to the transport vehicle equipped with the control unit, specifying the stop location marked with the stop position indicator related to the anomaly as the destination. The control unit receives the travel command output again and resumes travel using the travel unit.

3. The control system according to claim 2, wherein, If the number of notifications of anomalies from the same transport vehicle to the same stop position marker exceeds a set number, the upper control unit will not output the travel command again, but will instead issue an anomaly notification using a display device or a sound output device.

4. The control system according to any one of claims 1 to 3, wherein, When the upper control unit receives a notification of the occurrence of the abnormality from the control unit, it stores the abnormality information in a storage device. The abnormality information includes information about at least one of the transport vehicle equipped with the control unit and the stop position marker involved in the abnormality.

5. The control system according to any one of claims 1 to 3, wherein, If the distance traveled from the position of the stop warning sign detected by the sign body detection unit is less than or equal to the determination distance, but the number of times the stop position sign is detected by the sign body detection unit becomes more than or equal to a set number, the control unit shall issue an abnormality notification using the display unit or the sound output unit.

6. The control system according to any one of claims 1 to 3, wherein, The range of travel distance from the point where the position of the stop warning sign is detected by the sign body detection unit is less than the determination distance is set in a manner that matches the range where the transfer of the item between the transfer object and the transfer unit cannot be performed.

7. The control system according to any one of claims 1 to 3, wherein, After the marker detection unit detects the stop position marker, the control unit performs the transfer process if the state of detecting the stop position marker has lasted for a set time or more.

8. A control system for controlling a goods transport vehicle that travels along a predetermined path to transport goods, characterized in that, The vehicle is equipped with a stop position marker, which is positioned along the travel path at a location corresponding to the stopping point of the goods transport vehicle. The transport vehicle includes: a traveling unit that travels along the travel path; a transfer unit that holds the items and transfers the items between them and a transfer object disposed at the stop location; a marker detection unit that detects the stop position marker; and a control unit that controls the traveling unit and the transfer unit. The front side of the transport vehicle traveling along the travel path is designated as the downstream side, and the rear side of the travel direction is designated as the upstream side. The stop position indicator includes: a stop position indicator showing the stop position of the goods transport vehicle, and a stop warning indicator disposed on the upstream side relative to the stop position indicator. The upstream end of the stop warning indicator is positioned at a predetermined warning distance relative to the stop position indicator, moving upstream from the stop position indicator. After the stop warning sign is detected by the sign detection unit, and the control unit determines, based on the sign detection unit's detection result of the stop position sign, that the transport vehicle has reached the location of the stop position sign, it executes a travel stop process to stop the movement of the traveling unit. After the traveling unit stops due to the travel stop process, it executes a transfer process to transfer the items by the transfer unit. The transport vehicle also has a travel distance detection unit for detecting the travel distance of the traveling unit. If the control unit detects the stop position marker even though the distance traveled from the position of the stop warning marker detected by the marker detection unit is less than the predetermined distance, the control unit does not determine that the transport vehicle has reached the position of the stop position marker and continues the movement of the transport vehicle. If the distance traveled from the position of the stop warning marker detected by the marker detection unit exceeds the predetermined distance, the control unit determines that the transport vehicle has reached the position of the stop position marker when the marker detection unit detects the stop position marker.

9. The control system according to claim 8, wherein, If the distance traveled from the position of the stop warning sign detected by the sign body detection unit is less than or equal to the determination distance, but the number of times the stop position sign is detected by the sign body detection unit becomes more than or equal to a set number, the control unit shall issue an abnormality notification using the display unit or the sound output unit.

10. The control system according to claim 8 or 9, wherein, The range of travel distance from the point where the position of the stop warning sign is detected by the sign body detection unit is less than the determination distance is set in a manner that matches the range where the transfer of the item between the transfer object and the transfer unit cannot be performed.

11. The control system according to claim 8 or 9, wherein, After the marker detection unit detects the stop position marker, the control unit performs the transfer process if the state of detecting the stop position marker has lasted for a set time or more.

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